The tax base is the amount on which the amount of a certain tax to be paid by a natural or legal person is calculated.
To calculate the amount of the tax, what you do is multiply the tax base by a certain percentage, which is called the tax rate.
In Personal Income Tax, or IRPF, the taxable base is the net income of the taxpayer, discounted the legal deductions, and it is on this amount that the amount to be paid for taxes will be calculated.
Personal income tax does not tax all the money that a person earns, only part of it, since a percentage of a worker's payroll goes to Social Security, the remaining amount is the taxable base, and it is the tax of the Income of Individuals.
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